Many mechanisms have been used for unlocking a computing device which has no physical keyboard. For devices which blank the display screen when they go idle, reliably unlocking the display screen can be a challenge. Some devices detect when they have been moved or when someone touches the display screen. Simple movement of the computing device does not mean that the person moving the device desires it to become active.
Some devices will display a pattern of objects on the screen then permit the user to touch a starting object then, using their finger, draw a line from a starting object to several other objects. The sequence in which specific objects are then touched by the user's finger constitute a predefined pattern. If the pattern entered by the user matches the predetermined pattern the device will be unlocked for use.
Other devices display a series of objects or graphic images and the user touches some plurality of objects in a predetermined sequence. This scenario operates much the same as the previously described line pattern unlock scenario.
Devices utilizing these types of unlock mechanisms require the use to memorize the pattern sequence for unlocking the display.